My ex-husband's 'girlfriend' came to my son's medical appointment, was given information and taken into my son's therapist to speak with although neither my nor I have signed any paperwork authorizing this. Is this legal? We live in California and share both legal and physical custody of our son.

Was there some kind of need to know at the time? Is there an ongoing investigation?

No to both... additionally-my son stated that when he went to his Dad's house he was yelled at by the girlfriend for telling his doctor that the medicine was making him feel naseous (he vomitted in class today). Please help me to help him!

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Did the father give permission for the girlfriend to be there?